实验四Bezier曲线生成算法实现

1、计算机图形学实验报告(实验四 ,.Bezier曲线生成算法实现一、实验目的及要求三次 Bezier曲线及 de Casteljau算法以及 b样条曲线二、理论基础详见教材！三、算法设计与分析Bezier 曲线生成算法int degree=3,i,x,y;float t;float coeff_x4=50.0,200.0,200.0,500.0;float coeff_y4=50.0,300.0,50.0,200.0;pDC->MoveTo(coeff_x0,coeff_y0; for(i=1;i<=3;i+ pDC->LineTo(coeff_xi,coeff_yi;for(

2、t=0;t<=1;t+=0.001x=hornbez(degree,coeff_x,t; y=hornbez(degree,coeff_y,t; pDC->SetPixel(x,y,RGB(0,0,0;float CMy2View:hornbez(int degree,float coeff,float tint i,n_choose_i;float fact,t1,aux;t1=1.0-t;fact=1.0;n_choose_i=1;aux=coeff0*t1;for(i=1;ifact =fact*t;n_choose_i=n_choose_i*(degree-i+1/i;au

3、x=(aux+fact*n_choose_i*coeffi*t1;aux=aux+fact*t*coeffdegree;return aux;de Casteljau 算法void CTuView:bezpoint(int degree,int npoints,float *coeff,float points float t,delt;int i;delt=1.0/(floatnpoints;t=0.0;for (i=0;ipointsi=decas(degree,coeff,t;t=t+delt;float CTuView:decas(int degree,float *coeff,flo

4、at t int r,i;float t1;float coeffa10;t1=1.0-t;for (i=0;i<=degree;i+coeffai=coeffi; for(r=1;r<=degree;r+for (i=0;i<=degree-r;i+ coeffai=t1*coeffai+t*coeffai+1;return coeffa0;主函数：void CTuView:OnDraw(CDC* pDCCTuDoc* pDoc = GetDocument(; ASSERT_VALID(pDoc;/ TODO: add draw code for native data h

5、ereint degree=5,npoints=1000,i;float coeffx=10,40,265,300,400,500;float coeffy=20,130,160,90,300,100;float points11000,points21000;for (i=0;ipDC->MoveTo(intcoeffxi,(intcoeffyi;pDC->LineTo (intcoeffxi+1,(intcoeffyi+1;bezpoint(degree,npoints,coeffx,points1;bezpoint(degree,npoints,coeffy,points2;

6、for(i=0;ipDC->SetPixel(intpoints1i,(intpoints2i,RGB(123,123,123;B 样条曲线void CBView:bsp(int degree,int l,float *coeff,float*knot,int dense,float *points,int *point_numint i,ii;float u;*point_num=0;for(i=degree-1;iif(knoti+1>knoti for(ii=0;iiu=knoti+ii*(knoti+1-knoti/dense; points*point_num=deboo

7、r(degree,coeff,knot,u,i; *point_num=(*point_num+1;float CBView:deboor(int degree,float *coeff,float *knot,float u,int iint k,j;float t1,t2;float coeffa30;for (j=i-degree+1;j<=i+1;j+ coeffaj=coeffj;for (k=1;k<=degree;k+ for(j=i+1;j>=i-degree+k+1;j- t1=(knotj+degree-k-u/(knotj+degree-k-knotj-

8、1; t2=1.0-t1;coeffaj=t1*coeffaj-1+t2*coeffaj;return coeffai+1;主函数：void CBView:OnDraw(CDC* pDCCBDoc* pDoc = GetDocument(; ASSERT_VALID(pDoc;/ TODO: add draw code for native data here int k,n;int degree,i,a;int dense=290,l=5;float coeffx=10,40,265,300,400,500,600;float coeffy=20,130,160,90,300,100,300

9、; float points12000,points22000;float knot=0,0,0,0,0,1,2,2,2,2,2;int *point_num; k=5,n=5;/*n+1 个点 */ degree=5;a=0; point_num=&a;for (i=0;i<6;i+ pDC->MoveTo(intcoeffxi,(intcoeffyi; pDC->LineTo (intcoeffxi+1,(intcoeffyi+1;bsp(degree,l,coeffx,knot,dense,points1,point_num;bsp(degree,l,coeffy,knot,dense,points2,point_num;for(i=0;i<2000;i+pDC->SetPixel(intpoints1i,(intpoints2i,RGB(123,123,12